As computer-based systems, appliances, automated teller machines, point of sale terminals and the like have become more prevalent in recent years, the ease of use of the human-machine interface is becoming more and more important. Such interfaces should operate intuitively and require little or no training so that they may be used by virtually anyone. Many conventional user interface devices are available on the market, such as the key board, the mouse, the joystick, and the touch screen. One of the most intuitive and interactive interface devices known is the touch panel, which can be a touch screen or a touch pad. A touch screen includes a touch-sensitive input panel and a display device, usually in a sandwich structure and provides a user with a machine interface through touching a panel sensitive to the user's touch and displaying content that the user “touches.” A conventional touch pad is a small planar rectangular pad, which can be installed near a display, on a computer, an automobile input device, and the like.
A conventional touch-sensitive panel typically has a smooth flat surface and uses sensors such as capacitive sensors and/or pressure sensors to sense locations being touched by a finger(s) and/or an object(s). For example, a user presses a region of a touch screen commonly with a fingertip to emulate a button press and/or moves his or her finger on the panel according to the graphics displayed behind the panel on the display device. Once the input(s) are sensed, the sensed input(s) are forwarded to a processor for processing.
A problem associated with the conventional touch-sensitive panel is that it does not provide relief information to the user. For example, a typical touch-sensitive panel has a smooth and flat surface and consequently, a user can not feel the edge(s) of a button. Another problem associated with the conventional touch-sensitive panel is the inability to provide input confirmation when a user enters an input. For example, when a user presses a location on a conventional touch-sensitive panel, the panel typically does not have the capability to confirm the selected input instantaneous. As such, lack of locating features such as buttons and lack of input confirmation information are drawbacks associated with a typical conventional touch-sensitive panel.